Tubular structures have a wide variety of practical uses. Tubular structures are constructed by various methods and from various materials. Designers of such tubular structures satisfy certain design criteria (such as strength, stiffness, weight and torsional behavior) by varying material types (fibers/resins), orientations of fiber directions and geometric proportions of the tube itself. Another way designers have sought to improve high performance tubes is by developing new manufacturing techniques that can reduce cost and time of manufacturing such tubular structures.
Existing tubular structure may be fabricated by placing a tubular member horizontally. Prior to insertion of a frame within the tubular member to support it, the tubular member might not possess enough internal strength to support its weight. This can occur when the diameter of the tubular member is large relative to a thickness of the tubular member, e.g., when the tubular member is a fuselage of a commercial jet. Sagging, slumping, or changing the shape of the tubular member may thus occur as a result of the horizontal positioning. To alleviate this problem, additional bracing, jigs, and fixtures may be used to retain the shape of the tubular structure.
Further, the frame might not be fabricated until the tubular member is completed. In other words, the frame is fabricated in series with the tubular member. This may increase manufacturing time of the fuselage or any other tubular structure.
Therefore methods, processes, and structures are desired that allow for the frame to be fabricated in parallel with the tubular member to reduce overall manufacturing time and allow the tubular member to gain its structural integrity early in the fabrication process to reduce the use of bracing, jigs, and fixtures.